Graphene-ionic liquid interfacial potential drop from DFT-MD simulations

Abstract

Ionic liquids (IL) are promising electrolytes for electrochemical applications due to their remarkable stability and high charge density. Molecular dynamics simulations are essential for better understanding the complex phenomena occurring at the electrode-IL interface. In this work, we have studied the interface between graphene and 1-ethyl-3-methyl-imidazolium tetrafluoroborate IL, using density functional theory-based molecular dynamics simulations at variable surface charge densities. We have disassembled the electrical double layer potential drop into two main components: one involving atomic charges and the other - dipoles. The latter component arises due to the electronic polarisation of the surface and is related to concepts hotly debated in the literature, such as the Thomas-Fermi screening length, effective surface charge plane, and quantum capacitance.

References in corpus (12)

• The electronic properties of graphene
• Canonical sampling through velocity-rescaling
• Separable Dual Space Gaussian Pseudo-potentials
• Relativistic separable dual-space Gaussian Pseudopotentials from H to Rn
• Electronic transport in two dimensional graphene
• Evaluation of Constant Potential Method in Simulating Electric Double-Layer Capacitors
• The electric double layer has a life of its own
• Quantum capacitance and density of states of graphene
• Charge fluctuations from molecular simulations in the constant-potential ensemble
• On the thickness of the double layer in ionic liquids
• DFT study of ionic liquids adsorption on circumcoronene shaped graphene
• Performance of SCAN density functional for a set of ionic liquid ion pairs

Cited by in corpus (3)

• Interfacial water asymmetry at ideal electrochemical interfaces
• Constant Potential and Constrained Charge Ensembles for Simulations of Conductive Electrodes
• Double layer in ionic liquids: capacitance vs. temperature from atomistic simulations